荧光原位杂交在染色体异常产前诊断中的应用研究

目的 对国产荧光原位杂交(FISH)试剂盒在染色体异常产前诊断中应用的可行性进行评估.方法 对115例羊水样本行常规染色体核型检测外,进行间期FISH快速检测.采用国产FISH探针,特异性识别21、18、13、X、Y染色体.结果 115例样本中FISH杂交成功100例,结果获取需24～48 h,其中95例为正常;3例为21三体;1例为18三体,结果与染色体核型分析一致;另有1例异常细胞数比例未达到判定阈值而结果不能判定,该样本的核型分析显示为 47,XXY[7]/46,XY[43]的低比例嵌合体.未见假阴性和假阳性.结论 国产FISH试剂盒具有较好的敏感性和特异性,与核型分析相比具有用材少、耗时短、操作简便及人员专业性依赖程度小的优势,但存在探针靶点有限、实验操作失败和结果不能判定的概率较高等问题.

Application of fluorescence in situ hybridization in prenatal diagnosis of chromosome abnormalities

Objective To evaluate the performance of domestic fluorescence in situ hybridization (FISH) probes in prenatal diagnosis of chromosome abnormalities. Methods One hundred and fifteen amniotic fluid specimens were analysed in parallel by interphase FISH and conventional cytogenetics. Five domestic FISH probes were used to detect chromosomes 21, 18, 13,  X, Y, respectively. Results Interphase FISH experiments succeeded in 100 out of the 115 cases, and the average turn-around time of FISH was 24-48 h. The results of FISH were in conformity with those of cytogenetics in 99 cases, including 95 normal cases, 3 cases of trisomy 21 and one case of trisomy 18. A case of mosaic 47, XXY[7]/46, XY[43] was considered as uninformative on the basis of FISH reporting criteria. There were no false-positive and false-negative findings. Conclusion Domestic FISH probes have high specificity and sensitivity in prenatal diagnosis of chromosome abnormalities. Compared to conventional cytogenetics, interphase FISH with uncultured amniotic fluid cells needs less analytic material, and is rapid and easy to handle. In the designed detection scope, interphase FISH is accurate and reliable. However, there exist targets limitation and higher incidences of test failure and uninformative results.